py: Don't try to "bind" types store as attributes of objects.

This was hit when trying to make urlparse.py from stdlib run. Took
quite some time to debug.

TODO: Reconsile bound method creation process better, maybe callable is
to generic type to bind at all?

1 files changed, 44 insertions, 0 deletions

diff --git a/tests/basics/class_store_class.py b/tests/basics/class_store_class.py
new file mode 100644
index 0000000000..c765fceaa8
--- /dev/null
+++ b/tests/basics/class_store_class.py
@@ -0,0 +1,44 @@
+# Inspired by urlparse.py from CPython 3.3 stdlib
+# There was a bug in MicroPython that under some conditions class stored
+# in instance attribute later was returned "bound" as if it was a method,
+# which caused class constructor to receive extra argument.
+from collections import namedtuple
+
+_DefragResultBase = namedtuple('DefragResult', 'foo bar')
+
+class _ResultMixinStr(object):
+    def encode(self):
+        return self._encoded_counterpart(*(x.encode() for x in self))
+
+class _ResultMixinBytes(object):
+    def decode(self):
+        return self._decoded_counterpart(*(x.decode() for x in self))
+
+class DefragResult(_DefragResultBase, _ResultMixinStr):
+    pass
+
+class DefragResultBytes(_DefragResultBase, _ResultMixinBytes):
+    pass
+
+
+DefragResult._encoded_counterpart = DefragResultBytes
+DefragResultBytes._decoded_counterpart = DefragResult
+
+# Due to differences in type and native subclass printing,
+# the best thing we can do here is to just test that no exceptions
+# happen
+
+#print(DefragResult, DefragResult._encoded_counterpart)
+#print(DefragResultBytes, DefragResultBytes._decoded_counterpart)
+
+o1 = DefragResult("a", "b")
+#print(o1, type(o1))
+o2 = DefragResultBytes("a", "b")
+#print(o2, type(o2))
+
+#print(o1._encoded_counterpart)
+_o1 = o1.encode()
+print(_o1[0], _o1[1])
+#print(_o1, type(_o1))
+
+print("All's ok")